Recently, with the very fast development of wireless networks and the Internet, various multimedia services have been activated. In particular, with the advent of broadcasting communication convergence networks, a standardization task for providing scalability of video encoding has been conducted to guarantee Quality of Service (QoS) under various conditions of an environment in which multimedia is created, transmitted, and consumed, unlike the past in which only compression coding technology was developed.
Scalable Video Coding (SVC) technology is configured to adaptively reconstruct images having different resolutions (spatial), qualities, and frame rates (temporal) from a single compressed bitstream in conformity with various terminals and network environments. SVC is a video codec to which hierarchy is assigned to adaptively cope with various types of multimedia devices at high compressibility of H.264/Advanced Video Coding (AVC), and Joint Video Team (JVT) has carried out standardization of SVC as an amendment of H.264/MPEG-4 PART 10.
Further, High Efficiency Video Coding (HEVC) has been standardized as a next-generation video compression standard technology regarded as having compression efficiency that is more than twice the compression efficiency of the conventional H.264/AVC.
HEVC defines a Coding Unit (CU) having a quadtree structure, a Prediction Unit (PU), and a Transform Unit (TU), and uses an additional in-loop filter such as a Sample Adaptive Offset (SAO) or deblocking filter. Further, existing intra prediction and inter prediction are improved, thus enhancing compression coding efficiency.
Meanwhile, as an extension version of the recently standardized HEVC, SVC has also been standardized.
Conventional SVC technology is problematic in that, in inter-layer prediction, when an enhancement layer having temporal and spatial resolution different from that of a reference layer is encoded, a picture in the enhancement layer, for which a picture in the reference layer cannot be referred to, is present because a reconstructed picture in the reference layer is not present at the same temporal position as that of a picture in the enhancement layer to be encoded.